The present invention relates generally to leads implanted in the heart and for conducting electrical signals to and from the heart. More particularly, it pertains to an ultrasound echogenic cardiac lead.
Leads implanted in or about the heart have been used to reverse certain life threatening arrhythmias, or to stimulate contraction of the heart. Electrical energy is applied to the heart via the leads to return the heart to normal rhythm. Leads have also been used to sense in the atrium or ventricle of the heart and to deliver pacing pulses to the atrium or ventricle.
Cardiac pacing may be performed by the transvenous method or by leads implanted directly onto the ventricular epicardium. Permanent transvenous pacing is performed using a lead positioned within one or more chambers of the heart. A lead may be positioned in the ventricle or in the atrium through a subclavian vein, or cephalic vein, and the lead terminal pins are attached to a pacemaker which is implanted subcutaneously or submuscularly.
As the leads are implanted, or after the leads are implanted, the leads can be monitored using fluoroscopy. However, some hospitals or other places at which implantation of leads occurs have limited or no access to fluoroscopic equipment, for instance in countries with limited economic means. In addition, some patients should not be treated using fluoroscopy, for instance, women in early stages of pregnancy.
Accordingly, there is a need for a lead which allows for monitoring of the lead during or after implantation of the lead. What is also needed is a lead which allows for monitoring of the lead without substantial risk to the patient.
A lead assembly is provided including a flexible lead body extending from a proximal end to a distal end. The lead body has at least one conductor and a layer of echogenic material disposed directly on or in the conductor or directly on an inner surface of the conductor. Optionally, the conductor includes a helix forming an active fixation device disposed at the distal end of the lead body, where the echogenic material is disposed on the helix.
The flexible lead body has an outer surface, where the layer of echogenic material is completely encapsulated by the flexible lead body. An electrode assembly has at least one electrode which is electrically coupled with the conductor. In one alternative, the lead assembly includes an inner layer of insulator, and the echogenic material is disposed between the conductor and the inner layer of insulator. In another alternative, the conductor comprises one or more filars, each filar having an outer filar surface, the echogenic material disposed directly on at least a portion of the outer filar surface. In yet another option, the echogenic material is disposed on one or more portions of a length of the lead. Optionally, the echogenic material comprises an echogenic coating. The echogenic coating optionally comprises a porous coating, a metallic coating, or a metal oxide coating.
A lead assembly is provided including a flexible lead body extending from a proximal end to a distal end. The lead body has at least one conductor and a layer of echogenic material disposed directly on or in the conductor. The conductor comprises one or more filars, each filar having an outer filar surface, the echogenic material disposed directly on at least a portion of the outer filar surface. Optionally, the conductor includes a helix forming an active fixation device disposed at the distal end of the lead body, where the echogenic material is disposed on the helix.
The flexible lead body has an outer surface, where the layer of echogenic material is completely encapsulated by the flexible lead body. An electrode assembly has at least one electrode which is electrically coupled with the conductor.
In one alternative, the lead assembly includes an inner layer of insulator, and the echogenic material is disposed between the conductor and the inner layer of insulator. In yet another option, the echogenic material is disposed on one or more portions of a length of the lead.
Optionally, the echogenic material comprises an echogenic coating. The echogenic coating optionally comprises a porous coating, a metallic coating, or a metal oxide coating.
A lead assembly is provided including a flexible lead body extending from a proximal end to a distal end. The lead body has at least one conductor and a layer of echogenic material disposed directly on or in the conductor. The echogenic material is disposed on one or more portions of a length of the lead.
Optionally, the conductor includes a helix forming an active fixation device disposed at the distal end of the lead body, where the echogenic material is disposed on the helix.
The lead includes a layer of echogenic material which provides a cost effective alternative to monitoring an implanted medical device, such as a lead. The echogenic material also allows the lead to be monitored safely, without risk to patients having sensitive medical conditions. In addition, the layer of echogenic material is encapsulated by the lead body, such that the exposed blood and tissue contact surfaces of the lead remain unaffected from long-term biocompatibility and biostability.
These and other embodiments, aspects, advantages, and features of the present invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art by reference to the following description of the invention and referenced drawings or by practice of the invention. The aspects, advantages, and features of the invention are realized and attained by means of the instrumentalities, procedures, and combinations particularly pointed out in the appended claims and their equivalents.